This invention relates to hypodermic syringes, and more particularly to a syringe which may be safely disposed of and rendered inoperable after use.
It is common practice to dispose of hypodermic syringes after being used for injecting a medicinal fluid into or beneath a patient's skin, primarily for avoiding the transmission of communicable diseases through syringe reuse. After such single use, it is important to render the syringe needle inaccessible so that accidental human contact may not be made therewith.
A typical hypodermic syringe includes a hollow barrel fitted with a plunger, and a hollow needle longitudinally extending from the distal end of the barrel. One type of safety syringe permits the plunger to be secured, after use, to the needle so that the needle may be retracted into the barrel, and various means are provided for causing the needle to be captured within the barrel. The various mechanisms for implementing such operation in the past, however, are considered to be less reliable and more cumbersome than desired, and some of these safety devices are susceptible to careless manipulation which present unacceptable risks of accidental contact with the used needle.